Nonfiction by Cathy Glass
In this story, foster carer Cathy Glass takes care of a seven-year-old boy called Reece who has run through four other carers and been permanently excluded from two schools. He's badly behaved, and he bites. Unfortunately, his mother (a woman with five kids who have all been removed from her care by the state, and for good reason) thinks this is quite funny, and calls him "Sharky" with detached affection.
Cathy has her work cut out for her with this kid! It seems like there is no solution for a child that is this much trouble, but she doesn't give up. I like how Cathy really works hard to find the right place for Reece, and wants the best for him. There is a shocking surprise at the end of this book as well.